Retracting device for wheel excavators



3 Sheets-Sheet 1 Dec. 27, 1949 w, LEHMAN RETRACTING DEVICE FOR WHEEL EXCAVATORS Filed May 4, 1944 INVENTOR.

0&6 VVMZ41 v BY ATTORNEYS.

Dec. 27, 1949 w. LEHMAN 2,492,159

RETRACTING DEVICE FOR WHEEL EXCAVATORS Filed May 4, 1944 3 Sheets-Sheet 2 V Law- Sta-Wm,

INVENTOR. WWW film Lam.

Dec. 27, 1949 w. LEHMAN 2,492,159

RETRACTING DEVICE FOR WHEEL EXCAVATQRS Filed May 4, 1944 3 Sheets-Sheet 3 IN VEN TOR.

'BYW I W rokNEYs.

Patented Dec. 27, 1949 UNITED STATES PATENT OFFICE RETRACTING DEVICE FOR WHEEL EXCAVATORS Werner Lehman, South Milwaukee, Wis., assignor to Bucyrus-Erie Company, South Milwaukee, Wis., a corporation of Delaware Application May 4, 1944, Serial No. 534,033

7 Claims.

The wheel of such a machine is usually mounted on the end of a boom, and carries a series of digging buckets on its periphery. In all variants, these buckets dig as they move forward and/or upward with the revolution of the wheel. In some variants, they dump as they move downward after passing through their highest position. In other variants, the buckets have a spiral configuration which forces the excavated dirt out sidewise, either directly or through a hollow axle of the wheel (as for example, Smith, No. 242,484 and in Fischer, No. 1,763,769.) In most variants, the buckets dump onto a rearwardly moving conveyor-belt either directly or through a hopper.

The problem arises as to how to traverse the face of the bank of dirt with the digging wheel.

It is generally considered advisable to have the propelling machinery of the main base of the excavator face along the cut, whereby to move the excavator from station to station. In each station, the problem then arises of traversing the adjacent portion of the face of cut with a combination of motions in two or three dimensions.

For example, Kuhsel, No. 2,153,719, pivots his boom on his base, and traverses up and down, and incidentally to a slight extent forward and back, by raising and lowering his boom about its pivot. He traverses lengthwise of the out, in each station, by swinging the turntable of his machine. I

Weimer, No. 1,956,738, does the same, but em ploys an auxiliary turntable (on top of the main turntable) for lengthwise traversing in each station.

Johnson, No. 1,762,441, raises and lowers his wheel, and reciprocates his boom in and out, in much the same manner as the dipper of a conventional power-shovel.

My invention is, in general, of the Johnson type, my principal object being to improve the reciprocating means and the raising and lowering means.

The problems which I had to solve in this connection involved: (1) preventing interference, and assuring cooperation, between the means for thrusting the boom in and out, and the conveyorbelt carried by the boom; and (2) steadying the wheel in its raising and lowering, and more par ticularly during digging.

In addition to my principal objects, above stated, I have worked out a number of novel and useful details, which will be readily evident as the description progresses.

My invention consists in the novel parts and in the combination and arrangement thereof, which are defined in the appended claims, and of which one embodiment is exemplified in the accompanying drawings, which are hereinafter particularly described and explained.

Throughout the description the same reference number is applied to the same member or to similar members.

Figure 1 is a side elevation of my complete excavator, somewhat conventionalized, together with a dotted. showing of my wheel and some associated parts in three additional positions.

Figure 2 is an enlarged plan view of my reciprocating mechanism.

Figure 3 is a front elevation of the same, partly in section, taken along the lines 3-3 of Figure 2.

Figure 4 is a side elevation of the same.

Figure 5 is a front elevation of the wishbone of my hoisting mechanism.

Figure 6 is a side elevation of the same.

Referring now to Figure l, we see that II is the main propelling base of my excavator. Mounted thereon, for 360 swing, is a turntable l2, carrying a superstructure or A-frame l3.

Pivoted to the A-frame at l4, and projecting rearwardly (i. e., to the left in the picture), there is a stackerladder 15. A mast I6 is pivoted on the rear of the turntable l2, and is held by a suspension-line l1.

By means of a ladder-hoist line l8, proceeding, from a winch [9 on the turntable, over appropriate sheaves on the A-frame, mast, and ladder, the ladder may be raised and lowered.

, A long conveyor belt 20, extends from the front end of the machine at 2| past appropriate jointing at M, to the rear end of the ladder. This belt may, if desired, be provided with an appropriate intermediate unloader (not shown) wellknown in the art. The belt can be actuated by a motor 20a, or any other convenient means.

Pivoted on the front of the A-frame is another mast 22, with its suspension-line 23.

A boom 24 is pivoted at its rear end to a carriage 25, capable of sliding backward and forward on a track in the A-frame. The means for reciprocating this boom and carriage constitutes one of the principal features of my invention,

second principal feature of my inventionand will be hereinafter more particularly described.

A boom-hoist line 3| passes froma winch 32 on the turntable l2, over sheaves 33 at the upper end of mast 22 and sheaves 34 on the wishbone 3D, to raise and lower'the wishbone.

By rotating the" turntable "l2; shifting the carriage 25;, and raising and"lb'wering the wishbone 3t',the wheel traverses the face of-the cut in three dimensions.

Turning now to'Figures 2 3 and 4, 'let us con sider my reciprocating mechanism.

Each'side of the A-frame|3 supports a track- Way. Each"tra'ckwaycomprises a lower track 35,

an upper raclt-BSQand a side track'fil. I

The rear endo'f the boom 24 carries a motor 38 which, throughappropriatetransmission 39, ac-

tuates a cross-shaft' w, 'journaled on the boom.

At eachend' of this cross-shaft, there is apinion 4|, which engages a gear 42, mounted on a shaft 43, journaled in a carriage 44. This shaft 43 carries, within the saddleblock, a pinioi1'45 which engages the rack 36. The carriage 44 also carries two rollers 45, which runon lo'wertrack 35.

- Side track 31 servesas a guard-rail for shaft H The twocarriages l andthe boom '24 act together'as an articulatedunit; and it isvery advisable that the motor'38 and propelling pinions 45 be carriedby this unit, and the-rackets be --carried by some stationary part ofthe machine,

rather than vice versa, inorder thatthe discharge end ofbelt 21 shalltravel always ata substantially fixedd-istance from'beltdil regardless of the in- -clination and extent of retraction of theboorrr 24. r

' -Hopper 28 has Wheels 41', which run on rails "48,

which-are carried'by A-irame |3,-parallel to stackerbelt2l3. Dependingfrom the rear end of boomj l are two=lugs 4%, one on eachsideof hopper-28; From-these lugs to anchorages on-the I two sidesof the front of the hopper-,thereextend two links 56, whereby the hopper iscenstrained to reciprocate with the boomand yet is not tilted when --the boom is -tilted under the infiuence of hoistrope 3 l The rear-end of;the boom --has anopening 5| above-the hopper. Thusdirt-excavatedby the I wheel 25 is deposited on belt 21in any convenient -manner; is=carried to-therear by that=belt; is projectedoffthe rear-end of that belt; fallsthrough hole 5 through -hopper- 28 ontobe1t-2U; which belt --carriesit to therear of --the machine for stacking.

---Belt-2'|can' be actuatedby 'a'motor-52 carried by boom 24'; or. by any other-convenient means.

- Turning now to=Figures-5 and 6","let us consider mywishbone; As shown, it comprises "three con- --'-verging I-'beams;- secured-together in any con- V Upper l-beam B2- s1ides in -saddle-block ZQ-"(see Figure 1) Through this saddle-block there" 9 digging wheelcarried by the outer end of-- the 4 Shaft 63 for wheel 26 is journaled in the lower ends of I-beams 64 and 65. Journaled on the faces of my wishbone, adjacent the juncture of the three I-beams, are sheaves 34, to accommodate hoist-rope 3| (see Figure 1). Other means than these sheaves and. this rope could be used torais'e and lower my wishbone such, for

" bone is asymmetrical.

trally located with respect to the center of gravity ofboom 24 and its contents.

example, as a rack and pinion, as in the conventional single-part dipper-handle of a powershovel. M It will be noted, from Figure 5, that my wish- Upper I-beam 62 is cen- The wide side permits the passage'of belt 21. The front end of boom 24 is built integral with shaft 63.

It will be seen that my Wishbone construction steadies the wheel and its boom against side thrust and lateral tilt; not only during raising and lowering, but more important still when one side of the bottom or front of the"wh'ee'l. is .bearing hard against" the bank duringdigging,- as? is normal. Furthermore mydesign obviatesrunning the hoist-rope 3| clear down'to boom-24-,wher it 'in turn be intrferedwith by the-dirt.

might interfere with the digging m'echanism;and

Having now described andillustrated one: form of my invention, Iwish it to be u'nder'stood that my invention is not to be" limitedto "the specific form or arrangement of-'parts' -herein described and shown.

I claim: I 7 1. In a wheel excavator, comprising awmain frame, a stacker conveyor carried-thereby, a track on the main frame paralleling this conveyor; a "carriage 3 running .on-the track, a boom pivoted 7 adjacent its inner end on the carriage mean's for raising and lowering the outer end} of the boom, a conveyor carried lengthwise of the boom;- a

boom and adaptedto dump what it .dig'sbntdthe second mentioned conveyor, and means fpr'propelling the carriage along its -track,-the "combination therewith of: a second -track=on the main frame, substantially paralleling'the'stackenconveyor and a hoppen reciprocable "with the-boom and carriage, runningpn thi's last named track,

whereby the second conveyor dumps "onto the stacker conveyor through the hopper. t A 2. A wheel--excavator according toclaim 1, characterized. by thefurther fact of -having; J at least one link pivoted-to the boom-carriage unit and to the-hopper; whereby movement of the carriage 'on its track propels the hopper onits track.

3. A wheel excavator according tow-lain l,

7 characterized further bythe fact-that-themeans for raising and loweringthe outer; end of the boomcomprises: a mast, pivoted at its foot on the main frame; means'for supporting the upper end of the mast from-the framej alsaddle block at the upper nd' 'ef "the mast; a" Y shaped wishbone member? the stem r" wh'i'cl'i' is"reciprocable "through" the saddl blbckj'f andthe branches of which emanates outer-end o'f'the boom; at 1east one sheave carried-by the up'perend of the 'masE- at las't on Shea ried by the wishbonej a hoist' rope'" around the sheave; and means for actuating the carssing hoist-rope.

4; In a' wheelexcavator, the 'combination of:

- a main frame; a 'boom; pivota;lly= supported*adja'cent its-inner endfby the qnain fi'ame-g ail-igging' wheel carried 'by the outer 'endi df the boom;

a mast, pivoted at its foot on the main frame;

means for supporting the upper end of the mast from the frame; a saddle-block at the upper end of the mast; a Y-shaped wishbone member, the stem of which is reciprocable through the saddle-block, and the branches of which are pivoted to the outer end of the boom; at least one sheave carried by the upper end of the mast; at least one sheave carried by the wishbone; a hoistrope passing around the sheaves; and means for actuating the hoist-rope.

5. In a Wheel excavator, th combination of a main frame; a boom, pivotally supported adjacent its inner end by the main frame; a digging wheel carried by the outer end of the boom; a mast, pivoted at its foot on the main frame; means for supporting the upper end of the mast from the frame; a saddle-block at the upper end of the mast; a Y-shaped wishbone member, the stem of which is reciprocable through the saddleblock, and the branches of which are pivoted to the outer end of the boom; and means for reciprocating the wishbone.

6. A wheel excavator according to claim 5, further characterized by the fact that the wheel is coaxial with the pivotal connection of the wishbone to the boom.

7. In a wheel excavator, the combination of: a main frame; a boom, pivotally supported adjacent its inner end by the main frame; a conveyor, carried lengthwise of the boom, a digging wheel carried by the outer end of the boom, and adapted to dump what it digs onto the conveyor;

the conveyor being to one side of the Wheel; a mast, pivoted at its foot on the main frame; means for supporting the upper end of the mast from the frame; a saddle-block at the upper end of the mast; a Y-shaped wishbone member, the stem of which is reciprocable through the saddleblock, and the branches of which are pivoted to the outer end of the boom; said wishbone being asymmetrical, in that the stem is approximately aligned with the center of gravity of the end of the boom and its contents, and that its branches straddle both wheel and conveyor; and means for reciprocating the Wishbone.

WERNER LEHMAN.

REFERENCES CITED The following references are of record in the file of this patent:

FOREIGN PATENTS Number Country Date 505,153 Germany Aug. 15, 1930 534,882 Germany Oct. 2, 1931 569,222 Germany Jan. 31, 1933 574,718 Germany Apr. 19, 1933 579,642 Germany July 1, 1933 642,617 Germany Mar. 10, 1937 688,444 Germany Feb. 21, 1940 OTHER. REFERENCES German publication Braunkohle, Heft 15, 1941, pages 173-175. (Copy in Division 4.) 

